From: Tejun Heo tj@kernel.org
[ Upstream commit 4c6380305d21e36581b451f7337a36c93b64e050 ]
To prepare for unbound nr_active handling improvements, move work activation part of pwq_activate_inactive_work() into __pwq_activate_work() and add pwq_activate_work() which tests WORK_STRUCT_INACTIVE and updates nr_active.
pwq_activate_first_inactive() and try_to_grab_pending() are updated to use pwq_activate_work(). The latter conversion is functionally identical. For the former, this conversion adds an unnecessary WORK_STRUCT_INACTIVE testing. This is temporary and will be removed by the next patch.
Signed-off-by: Tejun Heo tj@kernel.org Reviewed-by: Lai Jiangshan jiangshanlai@gmail.com Stable-dep-of: 5797b1c18919 ("workqueue: Implement system-wide nr_active enforcement for unbound workqueues") Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/workqueue.c | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 6d0f64b5918ba..7e1b0238158ea 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1461,16 +1461,36 @@ static bool pwq_is_empty(struct pool_workqueue *pwq) return !pwq->nr_active && list_empty(&pwq->inactive_works); }
-static void pwq_activate_inactive_work(struct work_struct *work) +static void __pwq_activate_work(struct pool_workqueue *pwq, + struct work_struct *work) { - struct pool_workqueue *pwq = get_work_pwq(work); - trace_workqueue_activate_work(work); if (list_empty(&pwq->pool->worklist)) pwq->pool->watchdog_ts = jiffies; move_linked_works(work, &pwq->pool->worklist, NULL); __clear_bit(WORK_STRUCT_INACTIVE_BIT, work_data_bits(work)); +} + +/** + * pwq_activate_work - Activate a work item if inactive + * @pwq: pool_workqueue @work belongs to + * @work: work item to activate + * + * Returns %true if activated. %false if already active. + */ +static bool pwq_activate_work(struct pool_workqueue *pwq, + struct work_struct *work) +{ + struct worker_pool *pool = pwq->pool; + + lockdep_assert_held(&pool->lock); + + if (!(*work_data_bits(work) & WORK_STRUCT_INACTIVE)) + return false; + pwq->nr_active++; + __pwq_activate_work(pwq, work); + return true; }
static void pwq_activate_first_inactive(struct pool_workqueue *pwq) @@ -1478,7 +1498,7 @@ static void pwq_activate_first_inactive(struct pool_workqueue *pwq) struct work_struct *work = list_first_entry(&pwq->inactive_works, struct work_struct, entry);
- pwq_activate_inactive_work(work); + pwq_activate_work(pwq, work); }
/** @@ -1616,8 +1636,7 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork, * management later on and cause stall. Make sure the work * item is activated before grabbing. */ - if (*work_data_bits(work) & WORK_STRUCT_INACTIVE) - pwq_activate_inactive_work(work); + pwq_activate_work(pwq, work);
list_del_init(&work->entry); pwq_dec_nr_in_flight(pwq, *work_data_bits(work));